Hi and thanks for using 2CarPros. Com.
This vehicle is equipped with a coolant level sensor which is located in the reservoir. I have attached a picture of one for you to see. Unfortunately, I do not have a picture for your model, but it should be very similar. The picture is of a 2006 323i. Most likely, either the switch is bad or it has a bad connection. Check that first. In the picture, number one points at the sensor.
Let me know if you have other questions.
Saturday, June 16th, 2018 AT 8:49 PM